Name: aggregation
Rating: 64 (1 reviews)
Author: TanStack

aggregation

Aggregate TanStack Table columns independently of grouping, including grand totals, caller-selected row totals, multiple keyed aggregations, custom context-based definitions, grouped merges, manual values, and worker constraints.

Quality

76%

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Securityby

Passed

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tessl review fix ./packages/table-core/skills/aggregation/SKILL.md

Quality

Content

90%Weight 40%Scale 1-5

Reviews the quality of instructions and guidance provided to agents. Good implementation is clear, handles edge cases, and produces reliable results.

The body is a tight, executable reference with complete code and well-signaled sections, and it avoids explaining concepts Claude already knows. The only mild gap is the absence of an explicit validation checkpoint, which is not strictly required for read-only aggregation.

Dimension	Reasoning	Score
Conciseness	The body is lean and assumes Claude's competence; every prose block conveys version-specific v9 API behavior (caching, maxDepth, merge semantics) rather than generic concepts Claude already knows, matching the lean-and-efficient anchor.	5 / 5
Actionability	All code blocks are complete and executable with imports, and the examples cover the common cases (grand/filtered/child totals, multiple keyed aggregations, custom functions, manual values), matching the fully-executable anchor.	5 / 5
Workflow Clarity	The Setup -> Core Patterns -> Common Mistakes -> API Discovery flow is clear with Wrong/Correct guardrails, but it is a patterns catalog rather than a checkpointed multi-step workflow; aggregation is read-only so the destructive-validation cap does not apply, fitting the clear-sequence-with-minor-gaps anchor.	4 / 5
Progressive Disclosure	No bundle files exist, so scoring rests on the single-file structure; the body is well-sectioned and the API Discovery section appropriately points to external library paths rather than inlining bulk reference material, matching the good-structure anchor.	4 / 5
	Total	18 / 20 Passed

Description

63%Weight 40%Scale 1-5

Based on the skill's description, can an agent find and select it at the right time? Clear, specific descriptions lead to better discovery.

The description is highly specific and clearly distinct, but it omits any explicit "when to use" trigger guidance and leans on technical jargon over natural user phrasing. Adding a Use-when clause would lift the two lowest dimensions.

Suggestions

Append an explicit trigger clause such as "Use when aggregating TanStack Table columns for totals or subtotals, independent of grouping" to satisfy the completeness "when" requirement.

Add natural synonyms users actually say (e.g. "sums", "averages", "subtotals", "rollups") alongside the technical jargon to improve trigger-term coverage.

Mention the library trigger ("@tanstack/table-core" / "TanStack Table") so the skill surfaces when users reference the library by name.

Dimension	Reasoning	Score
Specificity	The description enumerates seven concrete actions ("grand totals, caller-selected row totals, multiple keyed aggregations, custom context-based definitions, grouped merges, manual values, and worker constraints"), matching the comprehensive-coverage anchor.	5 / 5
Completeness	It clearly states what the skill does but provides no "Use when..." or equivalent trigger guidance, so per the missing-trigger cap completeness cannot exceed 3.	3 / 5
Trigger Term Quality	Natural terms like "aggregate" and "totals" appear, but the bulk is technical jargon ("keyed aggregations", "context-based definitions", "worker constraints") with no common synonyms or file/library trigger phrases, fitting the some-keywords-but-missing-variations anchor.	3 / 5
Distinctiveness Conflict Risk	It carves out a specific TanStack Table aggregation niche ("independently of grouping") with low conflict risk, but the sibling grouping skill is a close neighbor, matching the mostly-distinct-with-minor-overlap anchor.	4 / 5
	Total	15 / 20 Passed

Validation

87%

Warnings & errors only

Checks the skill against the spec for correct structure and formatting. All validation checks must pass before discovery and implementation can be scored.

Validation — 14 / 16 Passed

Validation for skill structure

Criteria	Description	Result
metadata_version	'metadata.version' is missing	Warning
frontmatter_unknown_keys	Unknown frontmatter key(s) found; consider removing or moving to metadata	Warning

	Total	14 / 16 Passed

Repository: TanStack/table
Path: packages/table-core/skills/aggregation/SKILL.md
Commit: 36733a3

Reviewed: 2 days ago

Table of Contents

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